A double chain disc variator

Abstract

The utility model discloses a double chain disc transmission relates to bicycle technical field, including the speed regulator of being located on handle and the speed change piece on the vehicle body, and the speed regulator is connected with the speed change piece through the speed change line, including double chain disc transmission, and the double chain disc transmission includes the gear change disc, low speed chain disc, high speed chain disc and crank that combine in proper order, and low speed chain disc is fixedly connected with the crank, and high speed chain disc is connected with the crank through the bearing, and low speed chain disc and high speed chain disc are separately connected with the chain respectively, and the linkage mechanism is equipped on the crank, and the control of high speed chain disc is carried out through the interaction between the gear change mechanism on the gear change disc and the linkage mechanism on the crank. The utility model discloses through low speed chain disc, high speed chain disc connects and drives respective chain respectively, and the gear change disc is used to control the switching of gear, and the gear change is stable and easy 360 degrees dead angle free, will not stir the chain separation of chain, and all internal parts are realized through mechanical structure, and do not involve any electronic device, and the production manufacturing cost is low.

Description

Technical Field

[0001] This utility model relates to the field of bicycle transmission technology, specifically to a double-chain transmission. Background Technology

[0002] Traditional bicycle derailleurs typically employ a multi-stage sprocket and chainring combination, with shifting controlled by a shift cable. However, existing derailleurs have complex structures, prone to chain slippage and uneven shifting during gear changes, impacting the riding experience. Especially under high loads or high speeds, shifting reliability is insufficient, leading to gear failure or accelerated wear. Furthermore, the linkage mechanisms of traditional derailleurs are often cumbersome in design, difficult to maintain, and costly to manufacture. Therefore, a simple, reliable, and easy-to-operate dual-chainring derailleur is needed. Utility Model Content

[0003] The purpose of this invention is to provide a double-chain disc transmission to solve the problems mentioned in the background art.

[0004] To achieve the above objectives, this utility model provides a double-chainring derailleur, including a speed controller mounted on the handlebars and a gearshift plate on the vehicle body. The speed controller and the gearshift plate are connected via a gearshift cable. The double-chainring derailleur includes a shift bar, a low-speed chainring, a high-speed chainring, and a crank arranged in sequence. The low-speed chainring is fixedly connected to the crank, and the high-speed chainring is connected to the crank via a bearing. The low-speed chainring and the high-speed chainring are each individually connected to a chain. The crank is provided with a linkage mechanism, and the shift bar is provided with a shifting mechanism. The high-speed chainring is controlled by the interaction between the shifting mechanism on the shift bar and the linkage mechanism on the crank. The shift bar is in contact with the gearshift plate.

[0005] According to one embodiment of the present invention, the linkage mechanism includes a crank arm, a rotating shaft, and a high-speed chain control key. The crank arm and the rotating shaft are fixedly connected. A circular hole is provided at the bottom of the rotating shaft. The high-speed chain control key is connected to the circular hole at the bottom of the rotating shaft through a second spring.

[0006] According to one embodiment of the present invention, the high-speed chain control key is a square block with a protrusion at one end and a circular column at the other end on the same side. The end face of the protrusion is an inclined surface, and the end face of the circular column abuts against the second spring and is inserted into the circular hole at the bottom of the rotating shaft. The bottom of the high-speed chain control key is provided with a groove.

[0007] According to one embodiment of the present invention, the gear shifting mechanism includes a first turntable and a second turntable, the second turntable being rotatably connected to the first turntable; the first turntable is provided with a guide groove, and a V-shaped limiting block is provided in the guide groove, the V-shaped limiting block being connected to the groove by a pin, the V-shaped limiting block being rotatable in the groove, and a return spring connected to the bottom of the pin to limit the rotation of the V-shaped limiting block; the second turntable is provided with a rotating rod, one end of the rotating rod being rotatably connected to the second turntable, and the other end being provided with a support rod, the support rod extending into the guide groove and sliding in the groove, a limiting spring being connected to the middle of the rotating rod to keep it always close to the center of the second turntable, a clearance groove being opened in the middle of the second turntable, and a gear shifting shaft being provided behind the rotating rod and connected to the second turntable; a tension spring is connected between the first turntable and the second turntable.

[0008] According to one embodiment of the present invention, a pressure transformer is connected to the low-speed chain drive via a movable shaft. The pressure transformer is provided with a pressure rod, which can be pressed into the groove of the high-speed chain drive control key as the pressure transformer rotates.

[0009] According to one embodiment of the present invention, the high-speed chain disc has a coaxial annular shaft in the middle, and the end face of the annular shaft has helical teeth.

[0010] According to one embodiment of the present invention, washers are provided between the gear shift disc, the low-speed chain disc, and the high-speed chain disc.

[0011] The technical effects and advantages provided by this utility model in the above technical solution are as follows: 1. This utility model uses a low-speed chain disc and a high-speed chain disc to connect and drive their respective chains, and a gear shifting disc to control gear switching. Gear shifting is smooth and easy with 360-degree no dead angle, and there is no risk of the chain slipping off. Moreover, all internal parts are implemented through mechanical structures and do not involve any electronic components, resulting in low manufacturing costs.

[0012] 2. This utility model, through its ingenious structural design, can control different chain discs to achieve different speed distribution effects. It is quick and flexible in speed change, has few failures, no time difference, and a long service life. Attached Figure Description

[0013] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in this utility model. For those skilled in the art, other drawings can be obtained based on these drawings.

[0014] Figure 1 This is a schematic diagram of the connection structure between the low-speed chain disc and the high-speed chain disc of this utility model; Figure 2This is a schematic diagram of the low-speed chain disc structure of this utility model; Figure 3 This is a schematic diagram of the high-speed chain disk structure of this utility model; Figure 4 This is a schematic diagram of the crank linkage mechanism of this utility model; Figure 5 This is a schematic diagram of the gear shift disc structure of this utility model; Figure 6 This is a schematic diagram of the first turntable structure of this utility model; Figure 7 This is a schematic diagram of the second turntable structure of this utility model; Figure 8 This is a schematic diagram of the circular shaft structure of this utility model.

[0015] Explanation of reference numerals in the attached figures: 1. Gear shifter; 3. Protrusion; 4. Circular column; 5. Groove; 6. Second spring; 8. First turntable; 9. Second turntable; 10. Tension spring; 12. Low-speed chainring; 14. High-speed chainring; 15. Crank; 16. Circular shaft; 1501. Crank arm; 1502. Shaft; 1503. High-speed chainring control key; 801. Guide groove; 802. V-shaped limit block; 803. Pin; 901. Rotating rod; 902. Support rod; 903. Limiting spring; 904. Relief groove; 905. Gear shifting shaft; 1201. Pressure component; 1202. Pressure rod. Detailed Implementation

[0016] To enable those skilled in the art to better understand the technical solution of this utility model, the present utility model will be further described in detail below with reference to the accompanying drawings.

[0017] like Figure 1-8 As shown, a double-chainring gearbox includes a speed controller on the handlebars and a gear shifter on the vehicle body. The speed controller and the gear shifter are connected by a gear shifter cable. The double-chainring gearbox includes a shifter 1, a low-speed chainring 12, a high-speed chainring 14 and a crank 15 arranged in sequence. The low-speed chainring 12 is fixedly connected to the crank 15. The high-speed chainring 14 is connected to the crank 15 through a bearing. The low-speed chainring 12 and the high-speed chainring 14 are each connected to a chain separately. The crank 15 is provided with a linkage mechanism. The shifter 1 is provided with a shifting mechanism. The high-speed chainring 14 is controlled by the interaction between the shifting mechanism on the shifter 1 and the linkage mechanism on the crank (15). The shifter 1 is in contact with the gear shifter.

[0018] Twisting the speed regulator on the handlebars creates friction between the gear shifter and the gear shift disc 1, limiting the rotation of the outer ring of the gear shift disc 1. This activates the shifting mechanism, causing the control keys inside the gear shift disc 1 to shift, controlling the high-speed chain 14, allowing the bike to move forward at high speed. When a lower gear is needed, twisting the speed regulator returns the bike to a lower gear position. Each chain 1 is individually connected to its own chain, eliminating the need to shift gears by prying the chain. The circular gear shift disc 1 allows for 360-degree shifting without dead angles, providing quick, flexible, and trouble-free shifting with no time lag and a long service life. When not in use, the gear shifter and gear shift disc 1 are spaced 10mm apart, ensuring uninterrupted normal operation.

[0019] Further preferred, such as Figure 4 As shown, the linkage mechanism includes a crank arm 1501, a rotating shaft 1502, and a high-speed chain control key 1503. The crank arm 1501 and the rotating shaft 1502 are fixedly connected. A round hole is provided at the bottom of the rotating shaft 1502. The high-speed chain control key 1503 is connected to the round hole at the bottom of the rotating shaft 1502 through a second spring 6.

[0020] Preferably, the high-speed chain control key 1503 is a square block with a protrusion 3 at one end and a circular post 4 at the other end on the same side. The end face of the protrusion 3 is inclined, and the end face of the circular post 4 abuts against the second spring 6 and is inserted into the circular hole at the bottom of the rotating shaft 1502. The bottom of the high-speed chain control key 1503 is provided with a groove 5. When the high-speed gear is switched, under the action of the pressure rod 1202, the protrusion 3 of the high-speed chain control key 1503 engages with the helical teeth of the circular shaft 16 of the high-speed chain 14. The crank 15 rotates, driving the high-speed chain 14 to rotate, thereby running at high speed.

[0021] Preferred, such as Figure 5-7 As shown, the gear shifting mechanism includes a first turntable 8 and a second turntable 9, with the second turntable 9 rotatably connected to the first turntable 8; The first turntable 8 is provided with a guide groove 801, and a V-shaped limiting block 802 is provided in the guide groove 801. The V-shaped limiting block 802 is connected to the groove by a pin 803. The V-shaped limiting block 802 rotates in the groove. A return spring is connected to the bottom of the pin 803 to limit the rotation of the V-shaped limiting block 802. The second turntable 9 is provided with a rotating rod 901. One end of the rotating rod 901 is rotatably connected to the second turntable 9, and the other end is provided with a support rod 902. The support rod 902 extends into the guide groove 801 and slides in the groove. A limit spring 903 is connected to the middle of the rotating rod 901 so that it always leans towards the center of the second turntable 9. A clearance groove 904 is opened in the middle of the second turntable 9. A speed-changing rotating shaft 905 is provided behind the rotating rod 901 and connected to the second turntable 9. A tension spring 10 is connected between the first turntable 8 and the second turntable 9.

[0022] The rotation of the second turntable 9 drives the rotating rod 901 and the support rod 902 to move along the guide groove 801. Under the action of the limiting spring 903, the rotating rod 901 always moves towards the center of the turntable, and the support rod 902 moves in the groove. When it moves to the V-shaped limiting block 802, it is restricted and stuck in the cavity of the V-shaped limiting block 802. The V-shaped limiting block 802 also bounces back to the initial position under the restriction of the return spring at the bottom of the pin 803.

[0023] Preferred, such as Figure 2 As shown, a pressure transformer 1201 is connected to the low-speed chain 12 via a movable shaft. The pressure transformer 1201 is equipped with a pressure rod 1202. The pressure rod 1202 is pressed into the groove 5 of the high-speed chain control key 1503 as the pressure transformer 1201 rotates. When shifting gears, the shift shaft 905 on the shift plate 1 presses against the pressure transformer 1201. The pressure rod 1202 is pressed into the groove 5 of the high-speed chain control key 1503 by the pressure on the pressure transformer 1201, and the high-speed chain control key 1503 is pushed inward to engage with the helical teeth of the ring shaft 16.

[0024] Preferred, such as Figure 3 , 8 As shown, the high-speed chain 14 has a coaxial annular shaft 16 in the middle, and the end face of the annular shaft 16 has helical teeth. The helical teeth allow the control key to disengage at any time, and can be closed again under the action of the spring.

[0025] Preferably, washers are provided between the gear shift disc 1, the low-speed chain disc 12, and the high-speed chain disc 14.

[0026] Working process and principle: The low-speed and high-speed chainrings are installed. Crank 15 is fixedly connected to the low-speed chainring 12 and the second turntable 9. Crank 15 is connected to the high-speed chainring via bearings. The first turntable 8 and the second turntable 9 are rotatably connected to form a single gear shifting disc 1. When starting in low speed, there is no control from the gear shifting disc 1. Except for the high-speed chainring, all other components rotate with crank 15. The high-speed chainring 14 remains stationary. When shifting to high speed, the speed regulator on the handle is turned, and the shift plates rub against the outer ring of the gear shifting disc 1. The second turntable 9 and the first turntable 8... Relative rotation occurs, and the rotating rod 901 of the second turntable 9 moves along the guide groove 801 until it is restricted in the cavity of the V-shaped limit block 802. At this time, the speed-changing shaft 905 of the second turntable 9 presses on the pressure transformer 1201 of the low-speed chain disc 12, thereby pressing the pressure rod 1202 into the groove 5 of the high-speed chain disc control key 1503, so that the protrusion 3 of the high-speed chain disc control key 1503 engages with the helical teeth of the annular shaft 16 of the high-speed chain disc 14. At this time, although the low-speed and high-speed chain discs are running at the same time, the low-speed chain disc 12 is actually spinning idly.

[0027] To adjust from high speed to low speed, twist the speed regulator on the handlebar. The gear shift plate rubs against the outer ring of the shift disc 1, the lever 901 disengages from the V-shaped limit block 802, the tension spring 10 pulls the first turntable 8 back to the starting position, the shift shaft 905 separates from the pressure shifting component 1201, the crank 15 stops rotating for one second, allowing the helical teeth of the ring shaft 16 of the high-speed chain 14 to disengage from the high-speed chain control key 1503, and the vehicle runs at low speed.

[0028] The tilt direction of the helical teeth of the annular shaft 16 can be adjusted as needed; a protective shell can also be added to the outside of the device to protect the whole device.

[0029] In summary, this utility model connects the low-speed chainring 12 and the high-speed chainring 14 to drive their respective chains, and controls the gear shifting through the gear shifting disc 1, achieving smooth and easy gear shifting with 360-degree no dead angles. It prevents the chain from slipping off the track. Furthermore, all internal parts are implemented through mechanical structures without involving any electronic components, resulting in low manufacturing costs and allowing for the complete replacement of relevant parts of existing bicycles.

[0030] The foregoing description only illustrates certain exemplary embodiments of the present invention. Undoubtedly, those skilled in the art can modify the described embodiments in various ways without departing from the spirit and scope of the present invention. Therefore, the above drawings and descriptions are illustrative in nature and should not be construed as limiting the scope of protection of the claims of the present invention.

Claims

1. A double-chainring derailleur, comprising a speed controller mounted on the handlebars and a gearshift lever mounted on the vehicle body, wherein the speed controller and the gearshift lever are connected via a gearshift cable, characterized in that: The transmission includes a double-chainring gearbox, which comprises a shifting plate (1), a low-speed chainring (12), a high-speed chainring (14), and a crank (15) arranged in sequence. The low-speed chainring (12) is fixedly connected to the crank (15), and the high-speed chainring (14) is connected to the crank (15) via a bearing. The low-speed chainring (12) and the high-speed chainring (14) are each connected to a chain separately. The crank (15) is provided with a linkage mechanism, and the shifting plate (1) is provided with a shifting mechanism. The high-speed chainring (14) is controlled by the interaction between the shifting mechanism on the shifting plate (1) and the linkage mechanism on the crank (15). The shifting plate (1) is in contact with the gear shifter.

2. The double-chain disc transmission according to claim 1, characterized in that: The linkage mechanism includes a crank arm (1501), a rotating shaft (1502), and a high-speed chain control key (1503). The crank arm (1501) and the rotating shaft (1502) are fixedly connected. A round hole is provided at the bottom of the rotating shaft (1502). The high-speed chain control key (1503) is connected to the round hole at the bottom of the rotating shaft (1502) through a second spring (6).

3. A double-chain drivetrain according to claim 2, characterized in that: The high-speed chain control key (1503) is a square block with a protrusion (3) at one end and a circular post (4) at the other end on the same side. The end face of the protrusion (3) is an inclined surface. The end face of the circular post (4) abuts against the second spring (6) and is inserted into the circular hole at the bottom of the rotating shaft (1502). The bottom of the high-speed chain control key (1503) is provided with a groove (5).

4. A double-chain drivetrain according to claim 3, characterized in that: The gear shifting mechanism includes a first turntable (8) and a second turntable (9), the second turntable (9) being rotatably connected to the first turntable (8); The first turntable (8) is provided with a guide groove (801), and a V-shaped limiting block (802) is provided in the guide groove (801). The V-shaped limiting block (802) is connected to the groove by a pin (803). The V-shaped limiting block (802) rotates in the groove. A reset spring is connected to the bottom of the pin (803) to limit the rotation of the V-shaped limiting block (802). The second turntable (9) is provided with a rotating rod (901). One end of the rotating rod (901) is rotatably connected to the second turntable (9), and the other end is provided with a support rod (902). The support rod (902) extends into the guide groove (801) and slides in the groove. A limit spring (903) is connected to the middle of the rotating rod (901) so that it always leans towards the center of the second turntable (9). A clearance groove (904) is opened in the middle of the second turntable (9). A speed-changing rotating shaft (905) is provided behind the rotating rod (901) and connected to the second turntable (9). A tension spring (10) is connected between the first turntable (8) and the second turntable (9).

5. A double-chain drivetrain according to claim 4, characterized in that: The low-speed chain (12) is connected to a pressure transformer (1201) via a movable shaft. The pressure transformer (1201) is provided with a pressure rod (1202). The pressure rod (1202) is pressed into the groove (5) of the high-speed chain control key (1503) as the pressure transformer (1201) rotates.

6. A double-chain drivetrain according to claim 1, characterized in that: The high-speed chain (14) has a coaxial ring shaft (16) in the middle, and the end face of the ring shaft (16) is provided with helical teeth.

7. A double-chain drivetrain according to any one of claims 1 and 6, characterized in that: Washers are provided between the gear shift disc (1), the low-speed chain disc (12), and the high-speed chain disc (14).

Images